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Abstract:

An actuator that includes a substrate; first conductive layers provided
so as to extend in a first direction and to be disposed adjacent to each
other on the substrate; a piezoelectric body layer having a first portion
formed so as to cover the first conductive layers and openings between
the first conductive layers, a second portion other than the first
portions, and a contact to the first conductive layer; a second
conductive layer having a third portion which overlap with the first
conductive layers in the second direction, a fourth portion connected to
the third portion being formed over the second portion of the
piezoelectric body layer, and a fifth portion connected to the first
conductive layer in the contact ; and a wiring having a sixth portion
which is formed over the fourth portion of the second conductive layer
and a seventh portion connected to the fifth portion.

Claims:

1. An actuator comprising: a substrate having a first face; a plurality
of first electrically-conductive layers provided so as to extend in a
first direction and to be disposed adjacent to each other in a second
direction intersecting the first direction in the first face; a
piezoelectric body layer having a first portion formed so as to cover at
least a portion of each of a plurality of the first
electrically-conductive layers, and a second portion other than the first
portion; a second electrically-conductive layer having a third portion
which extends along the second direction so as to overlap with at least a
portion of each of the first electrically-conductive layers, when viewed
from the direction perpendicular to the first face, and continuously
cover a plurality of the first portions, and a fourth portion, which is
electrically connected to the third portion, is formed over the second
portion of the piezoelectric body layer and extends in the first
direction; a first lead wiring having a fifth portion which is formed
over the fourth portion of the second electrically-conductive layer and
extends in the first direction; and a protective film formed so as to
cover at least a portion of the first lead wiring, wherein the
piezoelectric body layer has a plurality of first opening portions
provided so as to extend in the first direction and to be disposed
adjacent to each other in the second direction, and the first portion of
the piezoelectric body layer is a portion sandwiched between the first
opening portions.

2. The actuator according to claim 1, wherein the third portion of the
second electrically-conductive layer further covers a portion of the
second portion of the piezoelectric body layer, the first lead wiring
further has a sixth portion, which is electrically connected to the fifth
portion, is formed over the third portion which is over the second
portion and extends in the second direction, and the sixth portion is
also covered by the protective film.

3. The actuator according to claim 1, wherein the second portion of the
piezoelectric body layer has a second opening portion which exposes a
portion of each of the first electrically-conductive layers, a second
lead wiring which is electrically connected to each of the first
electrically-conductive layers in the second opening portion is formed,
and the protective film further covers a portion of the second lead
wiring.

4. The actuator according to claim 1, wherein the protective film has a
third opening portion which makes a portion of the third portion be
opened, and when the first portions of the piezoelectric body layer
sandwiched between the first electrically-conductive layers and the
second electrically-conductive layer are set as driving regions and a
portion of the third portion which is exposed from the protective film
through the third opening portion is set as a seventh portion, both end
portions in the first direction of the seventh portion extend in the
second direction and continuously overlap with a plurality of the driving
regions when viewed from the direction perpendicular to the first face.

5. The actuator according to claim 1, wherein a foundation layer composed
of an electrical-conducting material is formed between the first face of
the substrate and the second portion of the piezoelectric body layer.

6. The actuator according to claim 1, wherein material of the protective
film is composed of at least one of an oxide material, a nitride
material, a photosensitive resin material, and an organic-inorganic
hybrid material.

7. A liquid droplet ejecting head comprising: the actuator according to
any one of claims 6.

8. A liquid droplet ejecting apparatus comprising: the liquid droplet
ejecting head according to claim 7.

9. A liquid droplet ejecting head comprising: the actuator according to
any one of claims 5.

10. A liquid droplet ejecting apparatus comprising: the liquid droplet
ejecting head according to claim 9.

11. A liquid droplet ejecting head comprising: the actuator according to
any one of claims 4.

12. A liquid droplet ejecting apparatus comprising: the liquid droplet
ejecting head according to claim 11.

13. A liquid droplet ejecting head comprising: the actuator according to
any one of claims 3.

14. A liquid droplet ejecting apparatus comprising: the liquid droplet
ejecting head according to claim 13.

15. A liquid droplet ejecting head comprising: the actuator according to
any one of claims 2.

16. A liquid droplet ejecting apparatus comprising: the liquid droplet
ejecting head according to claim 15.

17. A liquid droplet ejecting head comprising: the actuator according to
any one of claims 1.

18. A liquid droplet ejecting apparatus comprising: the liquid droplet
ejecting head according to claim 17.

19. A method of manufacturing an actuator, comprising: preparing a
substrate having a first face; forming a plurality of first
electrically-conductive layers provided so as to extend in a first
direction and to be disposed adjacent to each other in a second direction
intersecting the first direction in the first face; forming a
piezoelectric body layer having a first portion formed so as to cover at
least a portion of each of a plurality of the first
electrically-conductive layers, and a second portion other than the first
portion; forming a second electrically-conductive layer having a third
portion which extends along the second direction so as to overlap with at
least a portion of each of the first electrically-conductive layers when
viewed from the direction perpendicular to the first face and
continuously cover a plurality of the first portions, and a fourth
portion, which is electrically connected to the third portion, is formed
over the second portion of the piezoelectric body layer and extends in
the first direction; forming a first lead wiring having a fifth portion
which is formed over the fourth portion of the second
electrically-conductive layer and extends in the first direction; and
forming a protective film formed so as to cover at least a portion of the
first lead wiring, wherein the piezoelectric body layer has a plurality
of first opening portions provided so as to extend in the first direction
and to be disposed adjacent to each other in the second direction, and
the first portion of the piezoelectric body layer is a portion sandwiched
between the first opening portions.

20. A method of manufacturing a liquid droplet ejecting head, comprising:
forming an actuator by the actuator manufacturing method according to
claim 9; and forming a flow path forming plate having pressure chambers
which respectively overlap with a plurality of the first
electrically-conductive layers in a second face on the opposite side to
the first face of the substrate.

Description:

[0001] This application claims a priority to Japanese Patent Application
No. 2010-027318 filed on Feb. 10, 2010 which is hereby expressly
incorporated by reference herein in its entirety.

BACKGROUND

[0002] 1. Technical Field

[0003] The present invention relates to an actuator, a liquid droplet
ejecting head, a method of manufacturing the actuator and the liquid
droplet ejecting head, and a liquid droplet ejecting apparatus.

[0004] 2. Related Art

[0005] In a liquid droplet ejecting apparatus such as an ink jet printer
which can be used, for example, in an image recording apparatus, a
display manufacturing apparatus, or the like, it is known that an
actuator having a piezoelectric device is used in a liquid droplet
ejecting head for ejecting liquid droplets such as ink. In such an
actuator, volume in a pressure chamber can be changed, for example, by
deforming a substrate such as a vibration plate, which is formed below
the piezoelectric device, by deforming a piezoelectric body of the
piezoelectric device by application of a voltage such as a driving
signal. Accordingly, the liquid droplet ejecting head can eject liquid
droplets, such as ink supplied into the pressure chamber, from a nozzle
orifice.

[0006] In such an actuator, a common upper electrode structure is known in
which a plurality of piezoelectric bodies of the piezoelectric device is
formed and an electrode (hereinafter also referred to as an "upper
electrode") which covers the piezoelectric bodies is formed so as to
continuously cover the plurality of piezoelectric bodies
(JP-A-2009-172878). In an actuator having the common upper electrode
structure, compared to an electrode (hereinafter also referred to as a
"lower electrode") which is covered by the piezoelectric body, the upper
electrode needs to function as an electrode common to a plurality of
piezoelectric devices and there is a need for a larger current to flow
through a lead wiring thereof than in a lead wiring of the lower
electrode. Therefore, the lead wiring of the upper electrode requires
high reliability.

SUMMARY

[0007] An advantage of a first aspect of the invention is that it provides
an actuator having high reliability.

[0008] An advantage of a second aspect of the invention is that it
provides a liquid droplet ejecting head having the above-mentioned
actuator.

[0009] An advantage of a third aspect of the invention is that it provides
a liquid droplet ejecting apparatus having the above-mentioned liquid
droplet ejecting head.

[0010] An advantage of a fourth aspect of the invention is that it
provides a method of manufacturing an actuator having high reliability.

[0011] An advantage of a fifth aspect of the invention is that it provides
a method of manufacturing a liquid droplet ejecting head having the
above-mentioned actuator.

[0012] According to a first aspect of the invention, there is provided an
actuator including: a substrate having a first face; a plurality of first
electrically-conductive layers provided so as to extend in a first
direction and to be disposed adjacent to each other in a second direction
intersecting the first direction in the first face; a piezoelectric body
layer having a first portion formed so as to cover at least a portion of
each of a plurality of the first electrically-conductive layers, and a
second portion other than the first portion; a second
electrically-conductive layer having a third portion which extends along
the second direction so as to overlap with at least a portion of each of
the first electrically-conductive layers when viewed from the direction
perpendicular to the first face and continuously cover a plurality of the
first portions, and a fourth portion, which is electrically connected to
the third portion, is formed over the second portion of the piezoelectric
body layer and extends in the first direction; a first lead wiring having
a fifth portion which is formed over the fourth portion of the second
electrically-conductive layer and extends in the first direction; and a
protective film formed so as to cover at least a portion of the first
lead wiring, wherein the piezoelectric body layer has a plurality of
first opening portions provided so as to extend in the first direction
and to be disposed adjacent to each other in the second direction, and
the first portion of the piezoelectric body layer is a portion sandwiched
between the first opening portions.

[0013] In addition, in a description related to an embodiment, the word
"over" is used, for example, as meaning that a specific object
(hereinafter referred to as an "A") is formed over another specific
object (hereinafter referred to as a "B"). In a description related to
the invention, in a case such as this example, the word "over" is used as
including a case where the A is directly formed on the B and a case where
the A is formed on the B with another object interposed therebetween.
Similarly, the word "under" is used as including a case where the A is
formed directly below the B and a case where the A is formed below the B
with another object interposed therebetween.

[0014] According to the first aspect of the invention, since the first
lead wiring is covered by the protective film, peeling-off of the first
lead wiring is prevented. Accordingly, it is possible to provide an
actuator having high reliability.

[0015] In the first aspect of the invention, the third portion of the
second electrically-conductive layer may further cover a portion of the
second portion of the piezoelectric body layer, the first lead wiring
further may have a sixth portion which is electrically connected to the
fifth portion, is formed over the third portion which is over the second
portion, and extends in the second direction, and the sixth portion may
also be covered by the protective film.

[0016] In the first aspect of the invention, the second portion of the
piezoelectric body layer may have a second opening portion which exposes
a portion of each of the first electrically-conductive layers, a second
lead wiring may be formed which is electrically connected to each of the
first electrically-conductive layers in the second opening portion, and
the protective film may further cover a portion of the second lead
wiring.

[0017] In the first aspect of the invention, the protective film may have
a third opening portion which makes a portion of the third portion be
opened, and when the first portions of the piezoelectric body layer
sandwiched between the first electrically-conductive layers and the
second electrically-conductive layer are set as driving regions and a
portion of the third portion which is exposed from the protective film
through the third opening portion is set as a seventh portion, both end
portions in the first direction of the seventh portion may extend in the
second direction and continuously overlap with a plurality of the driving
regions when viewed from the direction perpendicular to the first face.

[0018] In the first aspect of the invention, a foundation layer composed
of an electrical-conducting material may be formed between the first face
of the substrate and the second portion of the piezoelectric body layer.

[0019] In the first aspect of the invention, the material of the
protective film may be composed of at least one of an oxide material, a
nitride material, a photosensitive resin material, and an
organic-inorganic hybrid material.

[0020] According to a second aspect of the invention, there is provided a
liquid droplet ejecting head including the actuator according to the
first aspect.

[0021] According to a third aspect of the invention, there is provided a
liquid droplet ejecting apparatus including the liquid droplet ejecting
head according to the second aspect.

[0022] According to a fourth aspect of the invention, there is provided a
method of manufacturing an actuator, including: preparing a substrate
having a first face; forming a plurality of first electrically-conductive
layers provided so as to extend in a first direction and to be disposed
adjacent to each other in a second direction intersecting the first
direction in the first face; forming a piezoelectric body layer having a
first portion formed so as to cover at least a portion of each of a
plurality of the first electrically-conductive layers, and a second
portion other than the first portion; forming a second
electrically-conductive layer having a third portion which extends along
the second direction so as to overlap with at least a portion of each of
the first electrically-conductive layers when viewed from the direction
perpendicular to the first face and continuously cover a plurality of the
first portions, and a fourth portion which is electrically connected to
the third portion, is formed over the second portion of the piezoelectric
body layer, and extends in the first direction; forming a first lead
wiring having a fifth portion which is formed over the fourth portion of
the second electrically-conductive layer and extends in the first
direction; and forming a protective film formed so as to cover at least a
portion of the first lead wiring, wherein the piezoelectric body layer
has a plurality of first opening portions provided so as to extend in the
first direction and to be disposed adjacent to each other in the second
direction, and the first portion of the piezoelectric body layer is a
portion sandwiched between the first opening portions.

[0023] According to the fourth aspect of the invention, since the first
lead wiring is covered by the protective film, peeling-off of the first
lead wiring is prevented. Moreover, process damage to the first lead
wiring during manufacturing can also be prevented. Accordingly, it is
possible to provide a method of manufacturing an actuator having high
reliability.

[0024] According to a fifth aspect of the invention, there is provided a
method of manufacturing a liquid droplet ejecting head, including:
forming an actuator by the actuator manufacturing method described above;
and forming a flow path forming plate having pressure chambers which
respectively overlap with a plurality of the first
electrically-conductive layers in a second face on the opposite side to
the first face of the substrate.

[0025] According to the fifth aspect of the invention, since the first
lead wiring is covered by the protective film, peeling-off of the first
lead wiring is prevented. Moreover, process damage to the first lead
wiring during manufacturing can also be prevented. Accordingly, it is
possible to provide a method of manufacturing a liquid droplet ejecting
head provided with an actuator having high reliability.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention will be described with reference to the accompanying
drawings, wherein like numbers reference like elements.

[0027]FIG. 1 is an exploded perspective view schematically showing a
liquid droplet ejecting head related to an embodiment.

[0028]FIG. 2A is a plan view schematically showing principal sections of
the liquid droplet ejecting head related to the embodiment.

[0029]FIG. 2B is a cross-sectional view schematically showing the
principal sections in line IIB-IIB of FIG. 2A.

[0030]FIG. 2c is a cross-sectional view schematically showing the
principal sections in line IIC-IIC of FIG. 2A.

[0031]FIG. 2D is a plan view schematically showing a piezoelectric body
layer related to the embodiment.

[0032] FIGS. 3A to 3C are cross-sectional views schematically showing a
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0033] FIGS. 4A to 4C are cross-sectional views schematically showing the
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0034] FIGS. 5A to 5C are cross-sectional views schematically showing the
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0035] FIGS. 6A and 6B are cross-sectional views schematically showing the
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0036] FIGS. 7A and 7B are cross-sectional views schematically showing the
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0037] FIGS. 8A and 8B are cross-sectional views schematically showing the
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0038] FIGS. 9A and 9B are cross-sectional views schematically showing the
method of manufacturing the liquid droplet ejecting head related to the
embodiment.

[0039] FIGS. 10A and 10B are cross-sectional views schematically showing
the method of manufacturing the liquid droplet ejecting head related to
the embodiment.

[0041] Hereinafter, one example of an embodiment to which the invention is
applied will be described with reference to the drawings. However, the
invention is not limited only to the following embodiment. The invention
should be construed as including combinations of the following embodiment
and modified examples thereof without restriction.

1. Actuator and Liquid Droplet Ejecting Head

[0042] Hereinafter, an actuator and a liquid droplet ejecting head, which
are related to this embodiment, will be described with reference to the
drawings.

[0043]FIG. 1 is an exploded perspective view of a liquid droplet ejecting
head 300 related to this embodiment.

[0044] As shown in FIG. 1, the liquid droplet ejecting head 300 related to
this embodiment includes a flow path forming plate 20 having a pressure
chamber 21, a vibration plate 10 formed above the flow path forming plate
20, a piezoelectric device 100 formed above the vibration plate 10, a
nozzle plate 30 formed below the flow path forming plate 20, and a
sealing plate 90 which seals the piezoelectric device 100.

[0045] As shown in FIG. 1, the liquid droplet ejecting head 300 related to
this embodiment includes an actuator 200 related to this embodiment. The
actuator 200 related to this embodiment is a piezoelectric actuator which
includes the piezoelectric device 100, and includes the vibration plate
10.

[0046] The vibration plate 10 is a plate-like member and has a first face
11, in which the piezoelectric device 100 is formed above the face, and a
second face 12 which is the face opposite to the first face 11. In the
actuator 200, the vibration plate 10 constitutes a deformation section.
In other words, the vibration plate can be deformed by deformation of the
piezoelectric device 100, which will be described later. Accordingly, it
is possible to change the volume of the pressure chamber 21 formed below.
The structure and the material of the vibration plate 10 are not
particularly limited as long as they have elasticity and can be deformed.
For example, the vibration plate 10 may be formed by a laminated body of
a plurality of films, as shown in FIG. 1. At this time, the vibration
plate 10 may also be a laminated body of a plurality of films, which is
composed, for example, of an insulating film such as zirconium oxide or
silicon oxide, a metal film such as nickel, and a polymeric material film
such as polyimide.

[0047] Also, as shown in FIG. 1, a through-hole 13 which communicates with
a reservoir 25 which will be described later is formed in the vibration
plate 10. The shape of the through-hole 13 is not particularly limited as
long as it is capable of supplying liquid to the reservoir 25. Although
it is not shown in the drawing, a metal layer may be formed on the
periphery of an opening portion of the through-hole 13.

[0048] The flow path forming plate 20 is formed over the second face 12 of
the vibration plate 10, as shown in FIG. 1. In other words, the flow path
forming plate 20 is disposed below the vibration plate 10 and so as to
face the second face 12, as shown in FIG. 1. The flow path forming plate
20 has the pressure chamber 21, as shown in FIG. 1. An upper face and a
bottom face of the pressure chamber 21 are respectively formed by the
second face 12 of the vibration plate 10 and the nozzle plate 30 which
will be described later. As shown in FIG. 1, the flow path forming plate
20 has wall portions 22 constituting side walls of the pressure chamber
21. Also, the flow path forming plate 20 may have the reservoir 25 which
communicates with the pressure chamber 21 through a supply path 23 and a
communication path 24. The reservoir 25 communicates with the
through-hole 13, so that liquid may be supplied from the outside to the
inside of the reservoir 25 through the through-hole 13. By supplying
liquid into the reservoir 25, it is possible to supply liquid to the
pressure chamber 21 through the supply path 23 and the communication path
24. The shape of the pressure chamber 21 is not particularly limited.
With respect to the shape of the pressure chamber 21, for example, the
shape in a plan view viewed from the normal direction of the first face
11 (hereinafter also referred to as "in a plan view") may be a
parallelogram or may also be a rectangle. The number of pressure chambers
21 is not particularly limited, but may be one or greater. The material
of the flow path forming plate 20 is not particularly limited. The flow
path forming plate 20 may be formed, for example, of single-crystal
silicon, nickel, stainless, stainless steel, glass ceramics, or the like.

[0049] The nozzle plate 30 is formed below the flow path forming plate 20
(on the opposite side to the side on which the vibration plate 10 is
formed), as shown in FIG. 1. The nozzle plate 30 is a plate-like member
and has nozzle orifices 31. The nozzle orifice 31 is formed so as to
communicate with the pressure chamber 21. The shape of the nozzle orifice
31 is not particularly limited as long as it is capable of discharging
liquid. Liquid in the pressure chamber 21 can be discharged, for example,
toward the lower side of the nozzle plate 30 (in a direction from the
inside of the pressure chamber 21 to the outside of the nozzle orifice
31) through the nozzle orifice 31. The number of the nozzle orifices 31
is not particularly limited, but may be one. Also, the nozzle orifice 31
may also be provided in a plurality so as to respectively correspond to a
plurality of pressure chambers 21, as shown in FIG. 1. The material of
the nozzle plate 30 is not particularly limited. The nozzle plate 30 may
be formed, for example, of single-crystal silicon, nickel, stainless,
stainless steel, glass ceramics, or the like.

[0050] The piezoelectric device 100 of the liquid droplet ejecting head
300 related to this embodiment is formed over the first face 11 of the
vibration plate 10, as shown in FIG. 1. The actuator 200 related to this
embodiment is constituted by the piezoelectric device 100 and the
vibration plate 10. Hereinafter, details of the actuator 200 related to
this embodiment will be described with reference to FIGS. 2A to 2C.

[0051]FIG. 2A is a plan view showing only the vibration plate 10, the
flow path forming plate 20, and the piezoelectric device 100, which are
principal sections of the liquid droplet ejecting head 300, for the sake
of convenience. In addition, the plan view of FIG. 2A is a plan view
viewed from the direction perpendicular to the first face. FIG. 2B is a
cross-sectional view along line IIB-IIB of the principal sections shown
in FIG. 2A. FIG. 2c is a cross-sectional view along line IIC-IIC of the
principal sections shown in FIG. 2A. FIG. 2D is a plan view schematically
showing principal sections of a piezoelectric body layer 50.

[0052] Details about a structure of the piezoelectric device 100 will be
described below.

[0053] As shown in FIGS. 2A to 2C, the piezoelectric device 100 includes a
first electrically-conductive layer 40 formed so as to extend in a first
direction 110 on the first face 11; the piezoelectric body layer 50
having a first portion 51 formed so as to cover at least a portion of the
first electrically-conductive layer 40, and a second portion 52 other
than the first portion 51; and a second electrically-conductive layer 60
formed so as to overlap with at least a portion of the first
electrically-conductive layer 40 when viewed from the direction
perpendicular to the first face 11 and cover at least a portion of the
first portion 51 of the piezoelectric body layer 50.

[0054] As shown in FIG. 2A, the vibration plate 10 has a movable region 15
in the second face 12 (refer to FIG. 2B). The movable region 15 is a
region which overlaps with the pressure chamber 21 of the flow path
forming plate 20 formed over the second face 12. As shown in FIG. 2A, the
movable region 15 may be formed for each pressure chamber 21. The movable
region 15 has the same shape as the shape in a plan view of the pressure
chamber 21.

[0055] Here, as shown in FIG. 2A, the longitudinal direction of the
movable region 15 (the pressure chamber 21), which is one direction in
the first face 11, is set as the first direction 110. Also, as shown in
FIG. 2A, a direction which intersects the first direction 110 and in
which the movable regions 15 (the pressure chambers 21) are disposed
adjacent to each other is set as a second direction 120. In a case where
the movable regions 15 are disposed so as to be adjacent to each other in
the direction perpendicular to the first direction 110, the second
direction 120 may be the direction perpendicular to the first direction
110.

[0056] As shown in FIG. 2B, in a case where a plurality of movable regions
15 disposed so as to be adjacent to each other in the second direction
120 is formed, a region between the movable regions 15 is set as an
immovable region 16. The wall portion 22 of the flow path forming plate
20 is formed below the immovable region 16.

[0057] The first electrically-conductive layer 40 is formed so as to
extend in the first direction 110 at least in the movable region 15, as
shown in FIG. 2A. As shown in FIG. 2A, the first electrically-conductive
layer 40 may be formed such that an end portion on one side in the first
direction 110 is formed in the movable region 15 and an end portion on
the other side is formed outside the movable region 15. However,
disposition of both end portions in the first direction 110 of the first
electrically-conductive layer 40 is not limited as long as the
piezoelectric body layer 50 which is sandwiched between the second
electrically-conductive layer 60, which will be described later, and the
first electrically-conductive layer 40 is formed in the movable region
15. Also, in a case where a plurality of movable regions 15 is formed on
the first face 11, the first electrically-conductive layer 40 may be
formed in a plurality and these first electrically-conductive layers may
also be formed so as to be disposed adjacent to each other along the
second direction 120.

[0058] The first electrically-conductive layer 40 is composed of a layer
having conductivity and constitutes a lower electrode in the
piezoelectric device 100. The structure and the material of the first
electrically-conductive layer 40 are not particularly limited as long as
they have conductivity. For example, the first electrically-conductive
layer 40 may also be formed by a single layer. Or, the first
electrically-conductive layer 40 may also be formed by a laminated body
of a plurality of films. The first electrically-conductive layer 40 may
also be, for example, a metal layer including any of platinum (Pt),
iridium (Ir), gold (Au), nickel (Ni), and the like.

[0059] Also, although for the sake of convenience, it is omitted in FIG.
2A, as shown in FIGS. 2B and 2C, a foundation layer 41 which is composed
of the same material as that of the first electrically-conductive layer
40 may be formed in a region of the first face 11, where the second
portion 52 of the piezoelectric body layer 50, which will be described
later, is formed. The foundation layer 41 may also be an
electrically-conductive film which is formed at the same time when
patterning the first electrically-conductive layer 40 after formation of
an electrically-conductive film on the first face 11 when forming the
first electrically-conductive layer 40. The foundation layer 41 is an
electrically-conductive layer to which voltage is not applied and which
is formed for controlling crystal growth of a piezoelectric body when
forming a piezoelectric body layer on the upper side. Accordingly,
crystal orientation of the piezoelectric body layer 50, which will be
described later, is made uniform, so that the reliability of the actuator
200 is improved.

[0060] The piezoelectric body layer 50 is a plate-like member formed above
the first face 11 of the vibration plate 10, as shown in FIGS. 2A and 2D,
and has an opening portion 56 which exposes a portion of the vibration
plate 10, for example, and divides the first portion 51 and the second
portion 52. The first portion 51 is a portion formed so as to cover a
portion of the first electrically-conductive layer 40 in the movable
region 15, as shown in FIGS. 2A, 2B, and 2D. The second portion 52 is a
portion constituting the piezoelectric body layer 50 other than the first
portion 51, as shown in FIGS. 2A, 2B, and 2D.

[0061] As shown in FIGS. 2A, 2B, and 2D, the piezoelectric body layer 50
has a plurality of opening portions 56. A plurality of opening portions
56 disposed so as to be adjacent to each other along the second direction
120 may be provided. The opening portion 56 extends in the first
direction 110 and overlaps with the immovable region 16, and both end
portions thereof in the second direction 120 may respectively overlap
with adjacent movable regions 15. The shape of the opening portion 56 in
a plan view in the normal direction of the first face 11 may be an oblong
shape (a rectangle) having long sides extending in the first direction
110. As described above, the piezoelectric body layer 50 sandwiched
between adjacent opening portions 56 can be set as the first portion 51.
That is, the shape of the opening portion 56 can be appropriately
determined according to the shape of the first portion 51 which will be
described later.

[0062] As shown in FIG. 2A, the first portion 51 is formed so as to extend
in the first direction 110 in the movable region 15 and may cover a
portion of the first electrically-conductive layer 40. The first portion
51 may also be formed in a plurality so as to respectively cover a
plurality of first electrically-conductive layers 40. The first portion
51 may also be formed in a plurality in which the first portions are
disposed adjacent to each other along the second direction 120.

[0063] The first portion 51 of the piezoelectric body layer 50 may have
both ends in the second direction 120 located in the movable region 15,
as shown in FIG. 2B. That is, in regard to the second direction 120, the
first portion 51 may also have a width larger than the width of the first
electrically-conductive layer 40 and narrower than the width of the
movable region 15. The first portion 51 may also be formed so as to
continuously extend along the first direction 110 and cover the first
electrically-conductive layer 40 also at the outside of the movable
region 15, as shown in FIG. 2A. However, it is acceptable if the first
portion covers the first electrically-conductive layer 40 at least in the
movable region 15, and there is no particular limitation. The shape of
the first portion 51 is not particularly limited. However, as shown in
FIG. 2B, the first portion may also have a face 53 located above the
first electrically-conductive layer 40, and tapered side surfaces 54
continued from the face 53. That is, the side surfaces 54 of the first
portion 51 may be formed when forming the opening portion 56.

[0064] As shown in FIGS. 2A and 2D, the second portion 52 is the
piezoelectric body layer 50 other than the first portion 51. As shown in
FIG. 2D, the second portion 52 may have a second portion 52a provided so
as to be disposed adjacent to a plurality of first portions 51 and
opening portions 56 in the second direction 120. Also, as shown in FIGS.
2A and 2D, the second portion 52 may also have a second portion 52b which
is provided between an end portion on one side in the first direction 110
of the first portion 51 and the reservoir 25 and the through-hole 13.
Also, as shown in FIG. 2D, the second portion 52 may also have a second
portion 52c which is provided so as to be disposed adjacent in the first
direction 110 to an end portion on the other side in the first direction
110 of the first portion 51 and in which an opening portion 57 opening at
the upper side of the first electrically-conductive layer 40 is formed.
That is, the second portion 52b and the second portion 52c can be
provided so as to interpose a plurality of first portions 51 and opening
portions 56 therebetween in the first direction 110.

[0065] The second portion 52a and the second portion 52b may also be
regions where the second electrically-conductive layer 60 and a first
lead wiring 70, which will be described later, are formed. Also, the
second portion 52c may also be a region where a second lead wiring 76,
which will be described later, is formed. Also, the second portion 52a
may also be a portion having a larger area than that of the second
portion 52b.

[0066] Also, although it is not shown in the drawing, the opening portion
57 may also be formed in the second portion 52b. In this case, the second
electrically-conductive layer 60 and the first lead wiring may also be
formed in the second portion 52c, and the second lead wiring 76 may also
be formed in the second portion 52b.

[0067] As shown in FIGS. 2A and 2C, the second portion 52c may also have
the opening portion 57 opening at the upper side of the first
electrically-conductive layer 40. The opening portion 57 is an opening
portion for forming an electric connection portion with the first
electrically-conductive layer 40 and may be a so-called contact hole. The
shape of the opening portion 57 is not particularly limited as long as
electric connection with the first electrically-conductive layer 40 is
made. Also, although it is not shown in the drawing, the opening portion
57 may also be formed in the first portion 51 or may also be formed
between the first portion 51 and the second portion 52.

[0068] Also, although it is not shown in the drawing, a piezoelectric body
layer may also be formed which is composed from a surface in which a
height from the first face 11 is lower than the face 53 of the first
portion 51 in the immovable region 16 between a plurality of first
portions 51, and the first portion 51 may also be continuously formed in
the second direction 120.

[0069] The piezoelectric body layer 50 is composed of a polycrystalline
body having a piezoelectric property and can be deformed by voltage which
is applied to the piezoelectric device 100. The structure and the
material of the piezoelectric body layer 50 are not particularly limited,
but it is acceptable if it has a piezoelectric property. The
piezoelectric body layer 50 may be formed of a known piezoelectric
material and, for example, lead zirconate titanate (Pb(Zr,Ti)O3),
bismuth sodium titanate ((Bi,Na)TiO3), or the like may also be used.

[0070] The second electrically-conductive layer 60 is formed so as to
overlap with at least a portion of the first electrically-conductive
layer 40 in the movable region 15 when viewed from the direction
perpendicular to the first face 11 and cover at least a portion of the
first portion 51 of the piezoelectric body layer 50, as shown in FIG. 2A.
Also, as shown in FIG. 2B, the second electrically-conductive layer 60 is
formed so as to continuously cover the first portions 51 of a plurality
of piezoelectric body layers 50 in the second direction 120. Therefore,
as shown in FIG. 2B, the second electrically-conductive layer 60 may be
formed also in the opening portion 56 (the immovable region 16) provided
between adjacent first portions 51. Here, as shown in FIGS. 2A to 2C, a
portion extending along the second direction so as to overlap with at
least a portion of the first electrically-conductive layer when viewed
from the direction perpendicular to the first face 11 and continuously
cover a plurality of first portions is set as a third portion 61. As
shown in FIGS. 2A and 2C, the third portion 61 may also be provided so as
to extend in the second direction 120 on the second portion 52b.

[0071] Also, the second electrically-conductive layer 60 may be
continuously formed over the second portion 52a of the piezoelectric body
layer 50, as shown in FIGS. 2A and 2B. The second electrically-conductive
layer may also be provided so as to extend, for example, in the first
direction 110 on the second portion 52a. Here, a portion which is
electrically connected to the third portion 61, is formed over the second
portion 52a of the piezoelectric body layer 50, and extends in the first
direction 110 is set as a fourth portion 62.

[0072] From the above, the second electrically-conductive layer 60 may
have an L-shape composed of the third portion 61 which extends in the
second direction 120 and the fourth portion 62 which extends in the first
direction 110. Also, although it is not shown in the drawing, the fourth
portion 62 may also extend in the second direction 120. Also, although it
is not shown in the drawing, the second electrically-conductive layer 60
may also be electrically connected to the first lead wiring 70, which
will be described later, without extending in the first direction 110 in
the second portion 52a.

[0073] As shown in FIGS. 2A and 2C, the first portion 51 which is
sandwiched between the first electrically-conductive layer 40 and the
second electrically-conductive layer 60 is set as a driving region 55 (a
hatched line portion in FIG. 2A). At this time, the shape of the second
electrically-conductive layer 60 is not particularly limited as long as
it is possible to form a driving region 55 in each of a plurality of
movable regions 15. As shown in FIG. 2c, both end portions in the first
direction 110 of the third portion 61 may be respectively located on the
first portion 51 and the second portion 52 of the piezoelectric body
layer 50. As shown in FIG. 2c, an end portion on one side in the first
direction 110 of the third portion 61 may define an end portion on one
side in the first direction 110 of the driving region 55. Here, an end
portion on the other side in the first direction 110 of the driving
region 55 may be defined by an end portion of the first
electrically-conductive layer 40.

[0074] The structure and the material of the second
electrically-conductive layer 60 are not particularly limited. For
example, the second electrically-conductive layer 60 may be formed in a
single layer. Or, the second electrically-conductive layer 60 may also be
formed by a laminated body of a plurality of films. The second
electrically-conductive layer 60 is composed of a layer having
conductivity and constitutes an upper electrode in the piezoelectric
device 100. The second electrically-conductive layer 60 may also be, for
example, a metal layer including platinum (Pt), iridium (Ir), gold (Au),
or the like.

[0075] The first lead wiring 70 is electrically connected to the second
electrically-conductive layer 60 in the second portions 52a and 52b of
the piezoelectric body layer 50, as shown in FIGS. 2A to 2C. The first
lead wiring 70 may be a wiring layer formed over the second
electrically-conductive layer 60. Also, as shown in FIG. 2A, the first
lead wiring 70 may have a fifth portion 71 extending in the first
direction 110 on the second portion 52a. Also, the first lead wiring 70
may also have a sixth portion 72, which is electrically connected to the
fifth portion 71, is formed over the third portion 61 on the second
portion 52b, and extends in the second direction 120. The sixth portion
72 may be formed so as to be disposed adjacent to a plurality of driving
regions 55 in the first direction 110. Here, the fifth portion 71 may be
a wiring layer having a larger wiring width than the sixth portion 72.
Also, as shown in FIG. 2A, the fifth portion 71 may also be smaller in
wiring width than the fourth portion 62 of the second
electrically-conductive layer 60 in the second portion 52a, and although
it is not shown in the drawing, the fifth portion may also be larger in
wiring width than the fourth portion 62.

[0076] Here, the first lead wiring 70 (the fifth portion 71) is intended
to have a flow of electric current which is larger compared to the second
lead wiring, which will be described later, and is formed so as to have a
larger area than that of the second lead wiring 76. That is, the larger
the surface area (shape) of the first lead wiring 70, the more the lead
wiring is suitable as a lead wiring of high capacity which creates a
large electric current flow. Therefore, as shown in FIG. 2A, the fifth
portion 71 may also be formed so as to cover the second portion 52a of
the piezoelectric body layer 50 as widely as possible.

[0077] Also, the fifth portion 71 is a portion which is electrically
connected to a driving circuit 210, shown in FIG. 1, by wire bonding, for
example. Therefore, by forming the fifth portion 71 so as to have a
larger area, it is possible to more conveniently connect more terminals
to the first lead wiring 70. Also, accordingly, it is possible to create
a larger electric current flow through the first lead wiring 70.

[0078] The structure and the material of the first lead wiring 70 are not
particularly limited. For example, the first lead wiring 70 may be formed
by a single-layered electrically-conductive layer or may also be formed
of a laminated body of a plurality of electrically-conductive layers. The
first lead wiring may also be formed of the same material as the second
electrically-conductive layer 60 or may also be formed of an electrical
conducting material having a lower resistance value and better
conductivity than the second electrically-conductive layer 60. The first
lead wiring 70 may also be a laminated body which includes, for example,
nickel/chromium alloy (NiCr), gold (Au), and the like.

[0079] As described above, by providing the sixth portion 72 formed of a
material having higher conductivity than the second
electrically-conductive layer 60, it is possible to supply electrical
power to a plurality of driving regions 55 without generating a drop in
voltage. That is, by supplying electrical energy from the fifth portion
71 to the second electrically-conductive layer 60 of the driving region
55, which is in a position distant from the fifth portion 71, through the
sixth portion 72, it is possible to reduce a drop in voltage due to
energy loss in a wiring.

[0080] The second lead wiring 76 is formed so as to be electrically
connected at least to the first electrically-conductive layer 40 in the
opening portion 57, as shown in FIGS. 2A and 2C. The shape of the second
lead wiring 76 is not particularly limited as long as the wiring is
electrically connected to the first electrically-conductive layer 40, but
the second lead wiring may extend in a desired direction. For example, as
shown in FIG. 2A, the second lead wiring may also be formed so as to
extend in the first direction 110.

[0081] Also, as shown in FIG. 2c, when forming the second
electrically-conductive layer 60, the second lead wiring 76 may also be
formed from a foundation layer 76a which is an electrically-conductive
film formed in the opening portion 57, and a wiring layer 76b formed so
as to be electrically connected to the foundation layer 76a. In the case
of forming the second lead wiring 76, by providing the foundation layer
76a, the foundation layer 76a serves as a protective film for the first
electrically-conductive layer 40 in a manufacturing process, thereby
being able to reduce process damage to the first electrically-conductive
layer 40, whereby the actuator 200 having high reliability can be formed.

[0082] The structure and the material of the second lead wiring 76 are not
particularly limited. For example, the second lead wiring 76 may be
formed by a single-layered electrically-conductive layer or may also be
formed of a laminated body of a plurality of electrically-conductive
layers. The second lead wiring may also be formed of the same material as
the first lead wiring 70. Also, the second lead wiring may be formed of
the same material as the first electrically-conductive layer 40 or may
also be formed of an electrical conducting material having a lower
resistance value and better conductivity than the first
electrically-conductive layer 40.

[0083] As described above, the piezoelectric device 100 is electrically
connected to the driving circuit 210 (IC) shown in FIG. 1 by the first
lead wiring 70 and the second lead wiring 76.

[0084] A protective film 80 is formed so as to cover a portion of the
first lead wiring 70, as shown in FIGS. 2A to 2C. The protective film may
also be formed so as to cover an end portion of the first lead wiring 70
formed over the second electrically-conductive layer 60. Also, the
protective film 80 may also be formed so as to cover an end portion of
the second electrically-conductive layer 60. Also, as shown in FIGS. 2A
and 2C, the protective film 80 may cover a portion of the second lead
wiring 76. Also, as shown in FIGS. 2A and 2C, the protective film 80 may
also be formed so as to overlap with both end portions in the first
direction 110 of the driving region 55. A region where the protective
film 80 is formed is not particularly limited as long as the protective
film 80 does not cover contact regions (not shown) of the first lead
wiring 70 and the second lead wiring 76 with the driving circuit 210 and
does not cover all of the driving regions 55 of the piezoelectric device
100.

[0085] For example, as shown in FIG. 2A, the protective film 80 may be a
single film which covers all regions other than the contact regions (not
shown) of the first lead wiring 70 (the fifth portion 71 and the sixth
portion 72) and the second lead wiring 76 with the driving circuit 210.
At this time, an end portion on one side in the first direction 110 of
the protective film 80 may be located on the foundation layer 41, as
shown in FIG. 2c, may be located on the first face 11 of the vibration
plate 10 although it is not shown in the drawing, or may be located on
the second portion 52b.

[0086] Also, for example, as shown in FIG. 2A, the protective film 80 may
have an opening portion 81 which makes a portion of the third portion 61
of the second electrically-conductive layer 60 be opened. The opening
portion 81 may be provided such that both end portions in the first
direction 110 of a plurality of driving regions 55 continuously overlap
with the protective film 80. That is, when a portion of the third portion
61 which is exposed from the protective film 80 through the opening
portion 81 is set as a seventh portion 65, as shown in FIG. 2A, both end
portions in the first direction 110 of the seventh portion 65 may extend
in the second direction 120 and continuously overlap with a plurality of
driving regions 55 when viewed from the direction perpendicular to the
first face 11. Also, an end portion on one side in the second direction
120 of the opening portion 81 may be located on the second
electrically-conductive layer 60 (the fourth portion 62) formed over the
second portion 52a, as shown in FIG. 2B, or may also be located on the
second electrically-conductive layer 60 formed in the opening portion 56
between the first portion 51 and the second portion 52a although it is
not shown in the drawing. Also, although it is not shown in the drawing,
the protective film 80 may also be formed above the immovable region 16
and the opening portion 81 may be formed in a plurality. That is, a
plurality of opening portions 81 may also be formed.

[0087] The protective film 80 is a film which is provided for preventing
peeling-off of the second electrically-conductive layer 60, the first
lead wiring 70, and the second lead wiring 76, which are formed over the
second portion 52 (52a, 52b, and 52c). Therefore, the material of the
protective film 80 is not particularly limited as long as it has
insulation properties and can prevent peeling-off of the first lead
wiring 70.

[0088] The protective film 80 may be formed of at least one of an oxide
material, a nitride material, a photosensitive resin material, and an
organic-inorganic hybrid material. For example, the protective film 80
may also be formed of an oxide material such as aluminum oxide
(Al2O3) or silicon oxide (SiO2). Accordingly, since it is
possible to form a protective film having high rigidity compared to a
resin film or the like, it is possible to more reliably prevent
peeling-off of the first lead wiring 70. Also, the protective film 80 may
also be formed of a nitride material such as silicon nitride
(Si3N4) or boron nitride (BN). Accordingly, since it is
possible to form a protective film having high rigidity compared to a
resin film or the like, it is possible to more reliably prevent
peeling-off of the first lead wiring 70. Also, for example, the
protective film 80 may also be formed of a photosensitive resin material
such as photosensitive polyimide. Accordingly, since it is possible to
form a protective film by a photolithographic technique, it is possible
to more conveniently form the protective film 80. Also, for example, the
protective film 80 may also be formed of an organic-inorganic hybrid
material such as silicone resin or benzocyclobutene resin. By using an
organic-inorganic hybrid material as the material of the protective film
80, it is possible to form the protective film 80 having flexibility or
formability and also having high strength.

[0089] The configuration of the actuator 200 having the piezoelectric
device 100 can be made by any of the configurations described above.

[0090] The liquid droplet ejecting head 300 related to this embodiment may
also have the sealing plate 90 which can seal the piezoelectric device
100, as shown in FIG. 1. The sealing plate 90 has a sealing region 91
which can seal the piezoelectric device 100 in a predetermined space. It
is acceptable if the sealing region 91 is a space of a size that does not
impede deformation movement of the piezoelectric device 100. Also, the
sealing plate 90 may also have an opening portion 92. Since the opening
portion 92 can communicate with the though-hole 13 and the reservoir 25,
liquid such as ink can be supplied to the reservoir 25 and the pressure
chamber 21 through the opening portion 92. The structure and the material
of the sealing plate 90 are not particularly limited. For example, the
sealing plate 90 may be formed, for example, of single-crystal silicon,
nickel, stainless, stainless steel, glass ceramics, or the like. Also,
the liquid droplet ejecting head 300 may also have the driving circuit
210 above the seal plate 90, as shown in FIG. 1, for example. Also, the
liquid droplet ejecting head 300 may also have a casing (not shown) which
is composed, for example, of various resin materials and various metal
materials and can house the above-described configuration.

[0091] By any of the configurations described above, the configuration of
the liquid droplet ejecting head 300 related to this embodiment can be
made.

[0092] The actuator 200 related to this embodiment has the following
features, for example.

[0093] According to the actuator 200 related to this embodiment, the
protective film 80 is formed so as to cover a portion of the first lead
wiring 70 formed above the second portion 52 of the piezoelectric body
layer 50. Accordingly, it is possible to provide the actuator 200 with
improved reliability.

[0094] As described above, since the first lead wiring 70 is a lead wiring
which is connected to the second electrically-conductive layer 60 that is
an upper electrode common to a plurality of driving regions 55, there is
a need for a larger current to flow through the first lead wiring
compared to the second lead wiring 76, thus the first lead wiring is
formed to have a larger area than the second lead wiring 76. However, as
regards the second electrically-conductive layer 60 formed below the
first lead wiring 70, adhesion with a piezoelectric material constituting
the piezoelectric body layer 50 is not as good as another material such
as resin. Therefore, there is a possibility that the fifth portion 71 and
the sixth portion 72 of the first lead wiring 70 will peel off from the
second portions 52a and 52b of the piezoelectric body layer 50. By
covering regions other than a contact region of such a first lead wiring
70 with the driving circuit 210 by the protective film 80, it is possible
to reduce the possibility that the first lead wiring 70 will peel off.

[0095] Also, by forming the protective film 80 so as to cover a portion of
the first lead wiring 70, it is possible to prevent process damage to the
first lead wiring 70 in a manufacturing process after formation of the
protective film 80, thereby improving reliability of the actuator 200 or
the liquid droplet ejecting head 300. Details of the manufacturing
process will be described later.

[0096] Also, since the protective film 80 can protect the second lead
wiring 76 and reduce the possibility that the second lead wiring 76 peels
off, similarly to the first lead wiring 70, it is possible to further
improve reliability of the actuator 200.

[0097] Also, the protective film 80 can overlap with both end portions in
the first direction 110 of the driving region 55. Accordingly, it is
possible to suppress displacement of both end portions where stress
easily concentrates due to displacement of the driving region 55 of the
piezoelectric body layer 50, thereby preventing generation of cracks or
the like in the peripheries of both end portions of the driving region
55. Therefore, it is possible to further improve reliability of the
actuator 200.

[0098] By the above configuration, according to the actuator 200 related
to this embodiment, it is possible to provide the liquid droplet ejecting
head 300 provided with the actuator 200 having high reliability.

2. Method of Manufacturing the Actuator and the Liquid Droplet Ejecting
Head

[0099] Hereinafter, a method of manufacturing the actuator 200 and the
liquid droplet ejecting head 300, which is related to this embodiment,
will be described with reference to the drawings.

[0100] FIGS. 3A to 10C are cross-sectional views schematically showing the
method of manufacturing the actuator 200 and the liquid droplet ejecting
head 300, which is related to this embodiment.

[0101] As shown in FIGS. 3A to 10C, the method of manufacturing the liquid
droplet ejecting head related to this embodiment includes a process for
preparing a substrate 1 having the first face 11, a process for forming a
plurality of first electrically-conductive layers 40 provided so as to
extend in the first direction 110 on the first face 11 and to be disposed
adjacent to each other in the second direction 120 intersecting the first
direction 110, a process for forming the piezoelectric body layer 50
having the first portion 51 formed so as to cover at least a portion of
each of a plurality of first electrically-conductive layers 40, and the
second portion 52 other than the first portion 51, a process for forming
the second electrically-conductive layer 60 having the third portion 61
which extends along the second direction 120 so as to overlap with at
least a portion of each of the first electrically-conductive layers 40
when viewed from the direction perpendicular to the first face 11 and
continuously cover a plurality of first portions 51, and the fourth
portion 62 which is electrically connected to the third portion 61, is
formed over the second portion 52 of the piezoelectric body layer 50, and
extends in the first direction 110, a process for forming the first lead
wiring 70 having the fifth portion 71 which is formed over the fourth
portion 62 of the second electrically-conductive layer 60 and extends in
the first direction 110, and a process for forming the protective film 80
formed so as to cover at least a portion of the first lead wiring 70.

[0102] The method of manufacturing the liquid droplet ejecting head
related to this embodiment varies according to the case of using
single-crystal silicon or the like as a material which is used for
forming the flow path forming plate 20 and the nozzle plate 30 and the
case of using stainless steel or the like. In the following, the method
of manufacturing the liquid droplet ejecting head in the case of using
single-crystal silicon is described as one example. The method of
manufacturing the liquid droplet ejecting head related to this embodiment
is not particularly limited to the following manufacturing method, but in
the case of using nickel, stainless steel, or the like as a material, a
process such as a known electroforming method may be included.

[0103] Also, the sequence of each process is not limited to a
manufacturing method described below. For example, after the pressure
chamber 21 and the like is formed in the flow path forming plate 20, the
piezoelectric device 100 may be formed, or, after the piezoelectric
device 100 is formed and then sealed by the sealing plate 90, the
pressure chamber 21 and the like may be formed in the flow path forming
plate 20.

[0104] First, as shown in FIG. 3A, the vibration plate 10 is prepared on
the prepared substrate 1 composed of single-crystal silicon. As shown in
FIG. 3A, in a manufacturing process which will be described later, among
the substrate 1, a region where the pressure chamber 21 is formed is set
as a region 21a; a region where the supply path 23 is formed is set as a
region 23a; a region where the communication path 24 is formed is set as
a region 24a; and a region where the reservoir 25 is formed is set as a
region 25a. Also, as shown in FIG. 3c, a region where the wall portion 22
is formed is set as a region 22a.

[0105] The vibration plate 10 may be formed by a known film-formation
technology. As shown in FIG. 3A, for example, the vibration plate 10 may
also be formed by forming an elastic layer 10a constituting an elastic
plate by a sputtering method or the like and then forming an insulating
layer 10b on the elastic layer 10a by a sputtering method or the like.
For example, as for the elastic layer 10a, zirconium oxide may be used,
and as for the insulating layer 10b, silicon oxide may be used. Here, on
the first face 11, a region overlapped with the region 21a is set as the
movable region 15. In addition, a detailed explanation of the vibration
plate 10 is omitted because the explanation described above can be
applied.

[0106] Next, as shown in FIG. 3B, the first electrically-conductive layer
40 is formed over the first face 11 of the vibration plate 10. Here, the
first electrically-conductive layer 40 is patterned into a desired shape
so as to extend in the first direction 110 in the movable region 15. The
first electrically-conductive layer 40 may be formed by a known
film-formation technology. The first electrically-conductive layer 40 may
also be formed by forming an electrically-conductive layer (not shown) by
depositing, for example, platinum, iridium, or the like by a sputtering
method or the like, and then etching the electrically-conductive layer
into a predetermined shape. In addition, a detailed explanation of the
first electrically-conductive layer 40 is omitted because the explanation
described above can be applied.

[0107] Here, as shown in FIG. 3c, after the electrically-conductive layer
is formed over the entire surface of the first face 11, when patterning
the first electrically-conductive layer 40, the foundation layer 41 which
is composed of an electrically-conductive layer may be formed avoiding at
least the movable region 15 on the first face 11. The foundation layer 41
is an electrically-conductive layer electrically insulated from the first
electrically-conductive layer 40. Accordingly, since a growth interface
of the piezoelectric body layer 50, which will be described later, can be
made to be an interface which is composed of an electrically-conductive
layer, it is possible to form the piezoelectric body layer 50 with
crystal growth controlled.

[0108] Also, as shown in FIG. 4A, it is also acceptable that before the
electrically-conductive layer for forming the first
electrically-conductive layer 40 is patterned by etching, an etching
protection film 50a is formed on the electrically-conductive layer and
the etching of the first electrically-conductive layer 40 is then
performed. The etching protection film 50a may be a piezoelectric body
layer formed of the same piezoelectric material as the piezoelectric body
layer 50, which will be described later. The etching protection film 50a
may be formed at least at a region where the first
electrically-conductive layer 40 which is patterned into a desired shape
is formed. Accordingly, in an etching process for patterning the first
electrically-conductive layer 40, the surface of the first
electrically-conductive layer 40 can be protected from damage due to an
etchant which is used.

[0109] Next, as shown in FIG. 4B, the piezoelectric body layer 50b is
formed so as to cover the first electrically-conductive layer 40. The
piezoelectric body layer 50 is formed by patterning the piezoelectric
body layer 50b. Details will be described later. The piezoelectric body
layer 50b may be formed by a known film-formation technology. The
piezoelectric body layer 50b may also be formed, for example, by applying
a precursor, which is a known piezoelectric material, on the first face
11 and then performing a heating treatment. As a precursor which is used,
provided that it generates a piezoelectric property by being subjected to
a polarization treatment after firing by a heating treatment, it is not
particularly limited, but, for example, a precursor such as lead
zirconate titanate may be used. In addition, in a case where the etching
protection film 50a is formed, since the etching protection film 50a is
formed of the same piezoelectric material as the piezoelectric body layer
50b (the piezoelectric body layer 50), the etching protection film 50a
can be integrated with the piezoelectric body layer 50b after firing.

[0110] Here, for example, in a case where the piezoelectric body layer 50b
(the piezoelectric body layer 50) is formed of lead zirconate titanate,
as shown in FIG. 4C, after an intermediate titanium layer 50c which is
composed of titanium is formed over the entire surface on the first face
11, a precursor which is a piezoelectric material may also be applied.
Accordingly, when performing crystal growth of the piezoelectric body
layer 50b by a heating treatment of the precursor, it is possible to
unify an interface, which makes crystal growth of the precursor occur, by
the intermediate titanium layer 50c. In other words, it is possible to
eliminate the piezoelectric body layer 50b which performs crystal growth
on the vibration plate 10. Due to this, controllability of crystal growth
of the piezoelectric body layer 50b can be increased, so that the
piezoelectric body layer 50b can become a piezoelectric body crystal
having higher orientation. In addition, the intermediate titanium layer
50c can be incorporated into a crystal of the piezoelectric body layer
50b at the time of a heating treatment.

[0111] Next, as shown in FIG. 5A, before the piezoelectric body layer 50b
is patterned into a desired shape by etching, a mask layer 60a having
conductivity may be formed so as to cover the piezoelectric body layer
50b. The mask layer 60a is a metal layer formed of the same material as
the second electrically-conductive layer 60 which will be described
later.

[0112] As shown in FIG. 5B, after forming the mask layer 60a, the
piezoelectric body layer 50b is patterned by etching, whereby the
piezoelectric body layer 50 is patterned into a desired shape. Here, due
to formation of the mask layer 60a, since the mask layer 60a acts as a
hard mask in an etching process, it is possible to easily form the
tapered side surfaces 54 at the piezoelectric body layer 50, as shown in
FIG. 5B. As shown in FIG. 5B, by forming the opening portion 56 when
patterning the piezoelectric body layer 50, the first portion 51 and the
second portion 52 can be formed at the piezoelectric body layer 50.
Although it is not shown in the drawing, a groove portion which extends
in the first direction 110 and divides the respective first portions 51
may also be formed without forming the opening portion 56.

[0113] As shown in FIG. 5c, when etching the piezoelectric body layer 50,
at the same time, the opening portion 57 which exposes the first
electrically-conductive layer 40 is formed above the first
electrically-conductive layer 40.

[0114] The opening portion 57 may also be formed above the first
electrically-conductive layer 40 extending outside the movable region 15,
for example.

[0115] In addition, detailed explanation of the first portion 51 and the
second portion 52 of the piezoelectric body layer 50 is omitted because
the explanation described above can be applied.

[0116] As shown in FIG. 6A, an electrically-conductive layer 60b is formed
so as to cover the piezoelectric body layer 50 and the opening portion
57. Here, the electrically-conductive layer may be formed so as to
continuously cover the first portion 51, the second portion 52, and the
opening portion 56, as shown in FIG. 6B. The electrically-conductive
layer 60b is formed of the same material as the second
electrically-conductive layer 60. The electrically-conductive layer 60b
may be formed by a known film-formation technology. The
electrically-conductive layer 60b may also be formed by depositing, for
example, platinum, iridium, or the like by a sputtering method. In a case
where the mask layer 60a has been formed, since the mask layer 60a is
formed using the same material as the second electrically-conductive
layer 60, the mask layer 60a can be integrated with the
electrically-conductive layer 60b.

[0117] Next, as shown in FIGS. 7A and 7B, the electrically-conductive
layer 60b is patterned into a desired shape by etching, so that the
second electrically-conductive layer 60 (the third portion 61 and the
fourth portion 62) is formed. Here, as shown in FIG. 7A, the driving
region 55 sandwiched between the first electrically-conductive layer 40
and the second electrically-conductive layer 60 in the first portion 51
of the piezoelectric body layer 50 can be defined. In addition, detailed
explanation of the second electrically-conductive layer 60 is omitted
because the explanation described above can be applied.

[0118] Also, in a process for patterning the second
electrically-conductive layer 60, the electrically-conductive layer 60b
may be patterned so as to cover at least the opening portion 57, as shown
in FIG. 7A. That is, the electrically-conductive layer 60b formed above
the opening portion 57 does not need to be removed. For example, in a
case where a resist film is formed by performing an exposure treatment
and a development treatment after application of a resist and etching is
then performed with the resist film as a mask, an organic alkaline
developer, organic peeling liquid, cleaning liquid, or the like is used.
Therefore, by not removing the electrically-conductive layer 60b formed
above the opening portion 57, it is possible to eliminate a possibility
that the surface of the first electrically-conductive layer 40 in the
opening portion 57 is overetched. Also, after etching, an exposed portion
of the first electrically-conductive layer 40 in the opening portion 57
can be prevented from being subjected to chemical damage due to exposure
to organic peeling liquid, cleaning liquid, or the like.

[0119] Next, as shown in FIGS. 8A and 8B, the first and second lead
wirings 72 and 76 are formed. The first and second lead wirings 72 and 76
may be formed by a known film-formation technology. The first and second
lead wirings 72 and 76 may also be formed by forming an
electrically-conductive layer (not shown) by a sputtering method or the
like by using a material having better conductivity than the second
electrically-conductive layer 60 such as gold, nickel/chromium alloy, or
the like, for example, and then etching the electrically-conductive layer
into a predetermined shape. In addition, detailed explanation of the
first and second lead wirings 72 and 76 is omitted because the
explanation described above can be applied.

[0120] As shown in FIGS. 9A and 9B, the protective film 80 is formed so as
to cover at least a portion of the first lead wiring 70. A film-formation
method for the protective film 80 is not particularly limited and the
protective film may be formed by a known film-formation technology. In a
case where the material of the protective film 80 is photosensitive
resin, the protective film may also be formed by forming a photosensitive
resin film such as polyimide, for example, by a coating method or the
like and then patterning the resin film into a desired shape by a
photolithographic technique. Also, in a case where the material of the
protective film 80 is an oxide material, by forming, for example, a metal
film by a known CVD method, a vapor deposition method, or the like,
patterning the film into a desired shape, then performing, for example, a
thermal oxidation treatment, it is possible to form the protective film
80 composed of an oxide material. In addition, detailed explanation of
the protective film 80 is omitted because the explanation described above
can be applied.

[0121] Next, as shown in FIG. 10A, the substrate 1 is thinned to a
predetermined thickness and the pressure chamber 21 and the like is then
partitioned. For example, with respect to the substrate 1 having the
predetermined thickness, by forming a mask (not shown) on the face
opposite to the face where the vibration plate 10 is formed, so as to be
patterned into a desired shape and then performing an etching treatment,
the pressure chamber 21, the wall portion 22, the supply path 23, the
communication path 24, and the reservoir 25 are partitioned (not shown).
By the above, the flow path forming plate 20 having the pressure chamber
21 can be formed below the vibration plate 10. After formation of the
flow path forming plate 20, as shown in FIG. 10B, the nozzle plate 30
having the nozzle orifice 31 is bonded to a predetermined position, for
example, by an adhesive agent or the like. Accordingly, the nozzle
orifice 31 communicates with the pressure chamber 21.

[0122] In this manner, by forming the protective film 80, the first lead
wiring 70 covered by the protective film 80 can be protected from process
damage in the manufacturing process.

[0123] Next, as shown in FIG. 10B, the sealing plate 90 in which the
sealing region 91 is formed is mounted on the upper side of the
piezoelectric device 100. Here, the piezoelectric device 100 can be
sealed within the sealing region 91. The sealing plate 90 may also seal
the piezoelectric device 100 by an adhesive agent 93, for example. Here,
the opening portion 92 can communicate with the through-hole 13.

[0124] By any of the methods described above, the actuator 200 and the
liquid droplet ejecting head 300 can be manufactured. In addition, as
described above, the method of manufacturing the actuator 200 and the
liquid droplet ejecting head 300 is not limited to the methods described
above and the flow path forming plate 20 and the nozzle plate 30 may also
be integrally formed by using an electroforming method or the like.

[0125] The method of manufacturing the actuator and the liquid droplet
ejecting head, which is related to this embodiment, has the following
features, for example.

[0126] According to the method of manufacturing the actuator 200 and the
liquid droplet ejecting head 300, which is related to this embodiment,
since a process for forming the protective film 80 so as to cover a
portion of the first lead wiring 70 is included, it is possible to
provide the actuator 200, in which peeling-off of the first lead wiring
70 is prevented and which has high reliability, and the liquid droplet
ejecting head 300 having the actuator 200.

[0127] Also, by forming the protective film 80 so as to cover a portion of
the first lead wiring 70, it is possible to prevent process damage to the
first lead wiring 70 in a manufacturing process after formation of the
protective film 80, thereby improving reliability of the actuator 200 or
the liquid droplet ejecting head 300.

[0128] By the above configuration, according to the method of
manufacturing the actuator 200 and the liquid droplet ejecting head,
which is related to this embodiment, it is possible to provide the
actuator 200 having high reliability and the liquid droplet ejecting head
300 having the actuator 200.

3. Liquid Droplet Ejecting Apparatus

[0129] Next, a liquid droplet ejecting apparatus related to this
embodiment will be described. The liquid droplet ejecting apparatus
related to this embodiment has the liquid droplet ejecting head 300
according to the invention. Here, a case is described where a liquid
droplet ejecting apparatus 1000 related to this embodiment is an ink jet
printer. FIG. 11 is a perspective view schematically showing the liquid
droplet ejecting apparatus 1000 related to this embodiment.

[0130] The liquid droplet ejecting apparatus 1000 includes a head unit
1030, a driving section 1010, and a control section 1060. Also, the
liquid droplet ejecting apparatus 1000 can include an apparatus main body
1020, a paper feed section 1050, a tray 1021, on which recording paper P
is mounted, a discharge opening 1022 which discharges the recording paper
P, and an operation panel 1070 disposed on the upper surface of the
apparatus main body 1020.

[0131] The head unit 1030 has an ink jet type recording head (hereinafter
simply referred to also as a "head") which is constituted from, for
example, the liquid droplet ejecting head 300 described above. The head
unit 1030 further includes an ink cartridge 1031 which supplies ink to
the head, and a transport section (a carriage) 1032, on which the head
and the ink cartridge 1031 are mounted.

[0132] The driving section 1010 can reciprocate the head unit 1030. The
driving section 1010 has a carriage motor 1041 which serves as a driving
source of the head unit 1030, and a reciprocation mechanism 1042 which
receives rotation of the carriage motor 1041, thereby reciprocating the
head unit 1030.

[0133] The reciprocation mechanism 1042 is provided with a carriage guide
shaft 1044 supported at both ends on a frame (not shown), and a timing
belt 1043 extending parallel to the carriage guide shaft 1044. The
carriage guide shaft 1044 supports the carriage 1032 while allowing the
carriage 1032 to freely reciprocate. Further, the carriage 1032 is fixed
to a portion of the timing belt 1043. If the timing belt 1043 is driven
by operation of the carriage motor 1041, the head unit 1030 reciprocates
and is guided by the carriage guide shaft 1044. At the time of this
reciprocation, appropriate ink is discharged from the head, whereby
printing onto the recording paper P is performed.

[0134] The control section 1060 can control the head unit 1030, the
driving section 1010, and the paper feed section 1050.

[0135] The paper feed section 1050 can send the recording paper P from the
tray 1021 to the head unit 1030 side. The paper feed section 1050 is
provided with a paper feed motor 1051 which serves as a driving source
thereof, and a paper feed roller 1052 which is rotated by an operation of
the paper feed motor 1051. The paper feed roller 1052 includes a driven
roller 1052a and a driving roller 1052b, which face up and down with a
feed passage of the recording paper P interposed therebetween. The
driving roller 1052b is connected to the paper feed motor 1051. If the
paper feed section 1050 is driven by the control section 1060, the
recording paper P is sent so as to pass below the head unit 1030.

[0136] The head unit 1030, the driving section 1010, the control section
1060, and the paper feed section 1050 are provided in the inside of the
apparatus main body 1020.

[0137] The liquid droplet ejecting apparatus 1000 can have the liquid
droplet ejecting head 300 according to the invention. The liquid droplet
ejecting head 300 according to the invention can have the piezoelectric
actuator having high reliability, as described above. Therefore, it is
possible to obtain the liquid droplet ejecting apparatus 1000 having high
reliability.

[0138] In addition, in the example described above, a case has been
described where the liquid droplet ejecting apparatus 1000 is an ink jet
printer. However, the printer according to the invention can also be used
as an industrial liquid droplet ejecting apparatus. As liquid (a liquid
material) which is discharged in this case, any of various functional
materials adjusted to have appropriate viscosity by a solvent or a
dispersion medium, a material including metal flakes or the like, or the
like can be used.

[0139] As described above, the embodiment of the invention has been
described in detail. However, it will be understood by those skilled in
the art that many modifications are possible without substantively
departing from the new aspects and effects of the invention. Accordingly,
all of such modified examples are to be included in the scope of the
invention.